Augmented reality eyebox fitting optimization for individuals

ABSTRACT

In some embodiments, the disclosed subject matter involves a head worn device (HWD) for viewing augmented reality, or virtual images. A projector coupled to the HWD may use a microelectromechanical systems projector and project onto a holographic lens of the HWD. Images may be projected into an eyebox area that is deemed comfortable to the user, the eyebox area located in one of a plurality of vertically adjacent recording zones. The recording zone for projection may be selected by the user, or be automatically selected based on configuration parameters of the HWD. Horizontal correction of the eyebox may be included. In an embodiment, multiple horizontal images are displayed in the selected recording zone, in different wavelengths. Another embodiment adjusts horizontal shift of the projected image based on user inputs. Other embodiments are described and claimed.

RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. 119(e)to U.S. Provisional Patent Application Ser. No. 62/614,282, filed Jan.5, 2018, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

An embodiment of the present subject matter relates generally toadjusting the eyebox in a viewing device, and, more specifically butwithout limitation, to adjusting the eyebox in an augmented realitysystem accommodating user preferences and eyesight limitations.

BACKGROUND

Various mechanisms exist for viewing augmented reality (AR). Manyexisting systems use a viewer which may be referred to as a head mounteddisplay (HMD), a head worn display (HWD), a heads-up display (HUD), apair of adapted eyeglasses, smart eyeglasses, also referred to assmartglasses, or other device through which, a user will look, or gaze.AR and Virtual Reality (VR) may differ in that while using an AR system,the user expects to be able to see the real world through the viewer, orglass, in addition to augmentation. This may also be referred to assee-through glasses or a see-through viewer. Thus, a usable viewer iseither transparent (e.g., to see the actual real world), or willredisplay an image of the real world in real time, for the user. Inaddition to seeing the actual environment, the augmentations must bedisplayed in an area of the viewer that is both visible to the user(e.g., appropriate focal length and positioning for the user'spupil(s)), and not directly in the way or blocking key real worldobjects or information.

Images may be displayed on lens surface as a transmission computergenerated hologram. The mathematics of computer generated holograms iswell understood. Essentially, holography is made up of three elements:the image, a light source, and the hologram. If any two of thoseelements is known, the third can be computed. However, holographicdisplays in existing HWDs may be bulky and difficult to customize for anindividual.

An identified problem with an HWD is to cope and compensate for variousinter-pupillary distances (IPD) in the population. A typical user's IPDmay range from 56 mm to 72 mm. Vertical misalignment may also be aproblem for some users. Existing devices such as HoloLens™ availablefrom Microsoft®, MagicLeap Lightwear™ glasses from Magic Leap,Smartglasses from ODG, Google Glass from Google X, and other HWDs, useclassical optical components making their devices bulky, but typicallyadequate optically, for many users. While good optics are desirable,existing HWDs are big and bulky and uncomfortable for many users.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents. Some embodiments are illustrated by way of example, and notlimitation, in the figures of the accompanying drawings in which:

FIG. 1A illustrates the eyebox principal as it relates to augmentedreality displays, according to an embodiment;

FIG. 1B illustrates vertical misalignment between the eyebox locationand pupil location, according, to an embodiment;

FIG. 2 illustrates eyebox issues with IPD variations among users,according to an embodiment;

FIG. 3 illustrates some of the design parameters that define a givenglass design, according to an embodiment;

FIG. 4A illustrates a virtual image location viewed through an eyebox,according to an embodiment;

FIG. 4B illustrates a virtual image location viewed through eyeboxesbased on user preference, according to an embodiment;

FIG. 5A illustrates an example recording implementation, according to anembodiment;

FIG. 5B illustrates a vertical and horizontal adaption of eyeboxes,according to an embodiment;

FIG. 6 is a flow diagram illustrating a manual fitting method, accordingto an embodiment;

FIG. 7 is a flow diagram illustrating an automatic adjustment method,according to an embodiment;

FIG. 8 is a block diagram illustrating an example of a machine uponwhich one or more embodiments may be implemented; and

FIG. 9 illustrates a head worn device in the form of smartglasses,according to an embodiment.

DETAILED DESCRIPTION

In the following description, for purposes of explanation, variousdetails are set forth in order to provide a thorough understanding ofsome example embodiments. It will be apparent, however, to one skilledin the art that the present subject matter may be practiced withoutthese specific details, or with slight alterations.

An embodiment of the present subject matter is a system and methodrelating to head worn displays (HWD) which may be used for augmentedreality (AR), and have a comfortable form factor similar to regulareyeglasses. Embodiments described use a tightly architected projectionsystem and electronics to result in an HWD that is just about the heightof a normal pair of eyeglass. To accomplish this, the electronics arevirtually invisible and the glass is about the same as a normal pair ofeyeglasses in terms of size and weight, by using microelectromechanicalsystems (MEMS) holographic technology. MEMS holographic projectors arebeing used in some HWD devices. For instance, a scanning projectionsystem may consists of a small etendue source such as a low power laser(e.g., a VCSEL, Vertical-cavity surface-emitting laser) or lightemitting diode (LED), reflected from a resonant micro-electromechanicalsystem (MEMS) scan mirror. For each position of the scan mirror a pixelmay be formed on the retina through raster scanning. Various formfactors of a MEMS projector may be utilized. Advantages of MEMSprojectors are their size and low power requirements, thus, making themsuitable for mounting on a pair of smartglasses.

In order to produce a small form factor HWD, the eyebox needs to be verysmall, due to the smaller optics footprint. In the context of vision,generally, and augmented or virtual reality eyewear, specifically, aneyebox is generally understood to be the volume of space within which aneffectively viewable image is formed by a lens system or visual display,representing a combination of exit pupil size and eye relief distance.The virtual image, e.g., the augmented image, may only be seen when theuser's pupil is looking at a specific position, or eyebox. It should benoted that the terms “virtual image” and “augmented image” are usedinterchangeably throughout this description. Outside of this eyebox, theimage typically cannot be seen. Because of variances of inter-pupillarydistance (IPD), existing systems found it difficult to design an HWDwith an eyebox acceptable to most users, without making the eyeboxlarger. However, making the eyebox larger makes the HWD larger andheavier, to accommodate the projection system. Many users find theselarger devices uncomfortable and not aesthetically pleasing. Moreover,not only is the IPD important for viewing the virtual image, but the eyeto ear position alignment variation from one user to another may causestrong vertical misalignment of (1) the eyebox location and (2) thevirtual image perceived location. For instance, poor eyebox location mayresult in a complete loss of the virtual image. Location of theaugmentation may cause viewing problems when super-imposing virtualimages in the user's field of view. In at least one embodiment, a newoptical configuration is used to enable better fitting of wearablesee-through glasses, coping for the human being (anthropomorphic)variability in terms of both inter-pupillary distance (IPD) andear-to-eye variation.

In an embodiment, the MEMS projector is made to overscan the MEMS mirrorto increase the area where an image may be displayed, e.g., theprojection area. In an embodiment, the scanning angle of the MEMS mirroris increased to cover a wider area and moving position of the recordingbeam, in the factory. The scanning angle may be increased by injectingmore current to the MEMS mirror without an increase in size or weight ofthe projector. Thus, the MEMS projector may project to a wider areawithout moving the projector. This increased projection area does notrequire the same kind of bulky hardware as existing systems use toincrease the eyebox. The recording angles may be stored in memory (e.g.,polymer memory) parameterizing memory volume. In an embodiment, arecording configuration is changed from one area to three areas.

Reference in the specification to “one embodiment” or “an embodiment”means that a particular feature, structure or characteristic describedin connection with the embodiment is included in at least one embodimentof the present subject matter. Thus, the appearances of the phrase “inone embodiment” or “in an embodiment” appearing in various placesthroughout the specification are not necessarily all referring to thesame embodiment, or to different or mutually exclusive embodiments.Features of various embodiments may be combined in other embodiments.

For purposes of explanation, specific configurations and details are setforth in order to provide a thorough understanding of the presentsubject matter. However, it will be apparent to one of ordinary skill inthe art that embodiments of the subject matter described may bepracticed without the specific details presented herein, or in variouscombinations, as described herein. Furthermore, well-known features maybe omitted or simplified in order not to obscure the describedembodiments. Various examples may be given throughout this description.These are merely descriptions of specific embodiments. The scope ormeaning of the claims is not limited to the examples given.

FIG. 1A illustrates the eyebox principal as it relates to augmentedreality displays, according to an embodiment. In an augmented realitysystem a user 130A may view the real world 121 directly through an opticglass 120 (i.e., lens), such as a volume holographic transparent lens.It should be noted that a volume holographic lens may be used for one ormore wavelengths, and a simple holographic lens may be used for a singlewavelength. Lens 120 may include stacking of multiple layers ofmaterial. In an embodiment, the lens 120 may include an holographicoptical element such as a lens, filter, beam splitter, diffractiongrating, etc. and some other material including polycarbonate, glass,anti-reflective coatings, anti-scratching coatings, or polarized film,etc. In an embodiment, the holographic material in the stacked layersmay be approximately 100 μm thick, whereas the entire lens 120 may beapproximately 500 μm thick. A volume hologram is a hologram where thethickness of the recording material is much larger than the lightwavelength used for recording. It will be understood that a variety ofform factors may be used to manufacture the lens 120 that will properlyreflect a holographic projection. For simplicity, lens 120 may bereferred to as a holographic lens, herein. A projection system, such asmay be implemented with a MEMs-based projection system 110, may projectan augmented image 111 onto the lens 120 for reflection into the user'spupil 131A. An eyebox 140 is the location where the user may effectivelysee the virtual, or augmented image. Thus, for a user to comfortably seethe augmented image, their pupil 131A must be properly aligned with theeyebox 140 created by the projection system 110.

FIG. 1B illustrates vertical misalignment between the eyebox locationand pupil location, according to an embodiment. In this example, theuser 130B may be looking up slightly, or have the glasses worn at anangle. The real world image 121 continues to pass directly through thelens 120, albeit at an angle from the pupil 131B The MEMS-baseprojection system 110 projects the augmented image 111 onto the lens120, but the augmented image may not be seen by the user 130B. Becauseof the angle of reflection, the eyebox 142 for the augmented image doesnot line up with the pupil 131B. Thus, this virtual image 111 may not beviewable for some user's point of view. Some users may have a largepupil and see images when the pupil does not line up with the eyebox,but this is not typical. Enlarging the eyebox 142 may mitigate thisproblem, but typically at the cost of a much larger projection system.

FIG. 2 illustrates eyebox issues with IPD variations among users,according to an embodiment. In this example, user 210 has an IPD of 60mm. User 220 has an IPD of 56 mm. Two eyeboxes are shown for each user,specifically eyeboxes 212, 214 for user 210, and eyeboxes 222, 224 foruser 220. If both users 210, 220 wear the same HWD, it may be seen thatthe user 210 pupil 211 may, be able to see using eyebox 212(corresponding to eyebox 222 for user 220), but not eyebox 214(corresponding to eyebox 224 for user 220). Similarly, because user 220has a smaller IPD, pupil 221 may be able to see using eyebox 224(corresponding to eyebox 214 for user 210), but not eyebox 222(corresponding to eyebox 212 for user 210). It will be understood thatthe same device with the same smaller eyebox will not provide effectiveviewing for both users 210, 220.

A mechanism to address the variations in IPD may be found in PublishedPatent Application No. US2017/0293147 A1 (hereinafter, “Application'147”) which provides a technical solution for enlarging the eyebox toaccount for IPD differences among users. A mechanism as discussed inApplication '147 is a method for displaying an image viewable by an eye,the image being projected from a portable head worn display andcomprises steps of emitting a plurality of light beams of wavelengthsthat differ amongst the light beams; directing the plurality of lightbeams to a scanning mirror; modulating in intensity each one of theplurality of light beams in accordance with intensity informationprovided from the image, whereby the intensity is representative of apixel value within the image; scanning the plurality of light beams intwo distinct axes with the scanning mirror to form the image; andredirecting the plurality of light beams to the eye using a holographicoptical element acting as a reflector of the light beams, whereby theredirecting is dependent on the wavelength of the light beam, to createfor each light beam an exit pupil at the eye that is spatially separatedfrom the exit pupils of the other light beams This mechanism, may helpwith minor variations; however, significant variance in vertical pupillocation may require additional adjustment.

In an embodiment, a fixed projector may be combined with a properlyrecorded holographic semi-transparent (tinted or not) combiner lens toadapt the system to the user's IPD. This example may use volumeholographic film. This holographic film may allow multiple differentbeams with various wavelength to illuminate the same location on theholographic film But the various wavelengths may reflect at differentangles due to the wavelength multiplexing of the volume hologram. In anembodiment, three beams having three wavelengths may be used to generatethree lateral eyeboxes of the same image. The three eyeboxes overlap inthe retina so that while moving the eye around one may switch smoothlyfrom one eyebox to another eyebox. The use of these three lateraleyeboxes allow the user to smoothly view from one wavelength beam toanother, thereby artificially expanding the eyebox size.

The mechanism in Application '147 may create multiple eyeboxes projectedsimultaneously at different wavelengths. The same image may be projectedfor each horizontal, or lateral eyebox. Thus, both user 210 and user 220may be able to see the virtual image using the same HWD, albeit at adifferent wavelength eyebox. This implementation allows users withdifferent IPDs to use the same HWD. However, the mechanism described inApplication '147 may not account for vertical variances among users.

It should be understood that the method as discussed in Application '147projects wavelength at different angles. In an embodiment, threewavelengths are reflected at different angles to the eye. However, thistechniques is not fully scalable to many more than three eyeboxesbecause volume holography is not perfect. In other words, the wavelengthchanges the color slightly and using too many wavelength variations mayproduce unacceptable color shifts in the projected image, based on whereit is viewed (e.g., at which angle). Thus, including additional verticaleyeboxes using additional wavelengths is not an optimal solution.

During test trials with a number of persons, the author found thatear-to-eye location and “horizontality” plays a significant fittingissue. Even though a user may have the correct holographic lensreflecting the image onto the correct IPD size, the user may (1) stillnot be able to see the image, and/or (2) see the virtual image to belocated a sub-optimal or undesirable line-of-sight.

From a pure glass design perspective, when using a single design frameshape, there is little margin for variance to compensate for verticalvirtual image eyebox and position due to human body shape. FIG. 3illustrates some of the design parameters that define, a given glassdesign, according to an embodiment. Any modification of theseparameters, may result in a different glass design frame, so none of theparameters, may effectively be used to compensate for all ear-to-eyehorizontality variation. The user's eye 310 has a back vertex distance311, also known as “eye relief,” from the surface of the glass/lens 320.The back vertex distance 311 is the distance from the pupil 312 to theback of the lens 320 along the primary straight ahead gaze line 316. Theangle of viewing, perhaps due to eyeglass tilt from ear or nosesize/locations, or frame design, may result in a pantoscopic tilt angle313. Pantoscopic tilt 313 is the angle of the eyewear lens 320 relativeto the primary straight ahead gaze line 316. A fitting height 315 maydepend on the height of the lens 320. A fitting height 315 is thevertical measurement between the pupil center 312 and the primarystraight ahead gaze line 316 to the bottom of the lens 320. Forinstance, it will be understood that lenses below a certain height arenot suitable for bifocals in prescriptive lenses. The same principalapplies for augmented reality glasses a certain fitting height may benecessary for the user to both see the real world image and an augmentedimage without obstruction or too much eye movement. For augmentedreality, it may be necessary to overlay the virtual image content on topof the real world background, and therefore the fitting height may beimportant. The location of a viewable eyebox may depend on thepantoscopic tilt angle 313, and eye relief distance 311 from the lens320 due to reflection angles and location of the projected image.

In an embodiment, to address the vertical misalignment of the fit due toear-to-eye variations from person to person, multiple vertical zones inthe holographic film of the lens may be defined. Thus, the system eitherrecords using volume multiplexing, or more classical surface holography.The projection system display parameters may be modified, so that theparameters result in multiple separated (non-overlapping) eyebox in theretina covering the entire population vertical fit. Embodiments enablethe user to select the eyebox that best fits their vertical fit. In anembodiment, the vertical eyeboxes may either be non-overlapping, butvertically adjacent (e.g., one on top of the other), or slightlyseparated by a small number of pixels. In an embodiment, the verticaleyeboxes may be slightly overlapping by a small number of pixels,because the user will typically only use a single one of those eyeboxes.Thus, having the eyeboxes overlap creates a kind of smaller imageposition granularity than one eyebox to the other.

It will be understood that when the holographic lens is manufactured, aninput recording angle may be stored in the polymer. Polymer memory maybe manufactured with electrically conducting polymer (PEDOT) and may bedenser and less expensive than flash memory. Polymer memory may becapable of storing a Mb of data in a mm² device. Polymer memory istypically a write once-read many device. Simply, a holographic lens ispiece of plastic. When you shoot a laser at the plastic at a particularangle, polymer memory may be used to retain the recording input andrecording beam angle. During use of the holographic lens, for instance,in a HWD, the recording input configuration may be retrieved from thepolymer memory. The projector may be focused to project a light sourceat the same angle as the recording reflection angle so that an image maybe viewed. For instance, in an example, the recording image position maybe recorded as 20 degrees down. It will be understood that many otherangles and configurations may be used, in practice.

FIG. 4A illustrates a virtual image location viewed through an eyebox,according to an embodiment. A first user 410 wears an HWD or glasseswith an ear piece 415 that is almost horizontal, or parallel to thefloor. Three eyeboxes 411, 412, and 413 may be available for viewing. Inthis example eyebox 412 is the most efficient eyebox to be seen throughthe user's pupil 414. However, a second user may prefer a differenteyebox.

FIG. 4B illustrates a virtual image location viewed through eyeboxesbased on user preference, according to an embodiment. A second user 420may wear an HWD glasses with an ear piece 425 that is at an angle, e.g.,not parallel to the floor or perfectly horizontal. Eyeboxes 421, 422,and 423 may be projected for viewing by user's pupil 424. In thisexample, user 420 may prefer to see a virtual image in eyebox 421. Buteven if eyebox 421 is the most efficient, or a natural choice, user 420might prefer to see the virtual image in eyebox 422. By changing thelocation where the user actually sees the virtual image, the user may beable to view the real world unobstructed When the user wants to see thevirtual image, the user may glance up or down to a selected eyebox. Inan embodiment, the eyebox selection may be user selectable rather thanautomatic An embodiment utilizing selectable eyeboxes may be used inconjunction with the IPD adaption, as described in Application '147, toprovide an HWD that may accommodate both horizontal and verticalvariances in users, as well as allowing user selectable parameters.Other embodiments may implement only the vertical adjustment and userselections. Some embodiments utilize automatic eyebox selection, and mayoptionally allow the user to change the automatic selection.

FIG. 5A illustrates an example recording implementation, according to anembodiment. In this example, a hologram may be recorded as a regular orvolume hologram, but in different distinctive zones, and for each ofthose zones having a modified angular laser input recorder so that theoutput beam(s) from projection system 550 may be placed apart along thevertical axis. In other words, creating different zones for the sameinput beam to be redirected to various output beams may be performed bychanging the position of the reference recording beam.

An embodiment modifies the recording physical setup, as compared toexisting holographic projection systems. Effectively the last beam ismoved, apart so that the beam hits the hologram with a certain angle. Inbetween the recording to the various vertical offset the other areas arehidden so that each area is effectively recorded with a specificincoming angle. Another embodiment records the holograms independently(e.g., the hologram alone is a kind of a thin plastic film) and thenplace the independent holograms on the lens side by side.

An example is shown with three recording zones 521, 523, and 525. An HWDmay include, a clear or prescriptive glass lens 510 for one eye, and alens with integrated hologram projection capability 520, for the othereye. The lens 520 may have a MEMs-scanning projection area 522. In thisexample, three projected images 531, 533, 535 may be projected to therecording zones 521, 523, and 525, respectively. The projected imagesmay typically be the same image so that the selection of eyebox area(e.g., which recording zone to view) will result in the user seeing thesame image, but in a different location in the lens 520.

Recording of those zones 521, 523, 525 may be performed in several ways.In a first embodiment, x images may be recorded at the same time, wherex is the number of recording areas. Images may be recorded with xrecording/reference light sources, all fixed at predetermined positionswith respect to the others, with one source (or set of sources,respectively, if multiple IPD coverage is implemented) for each area.

In a second embodiment, images may be recorded at x different times,hiding successively the zone, and recording one zone after the other.This technique has the advantage of requiring only onerecording/reference light source. It will be understood that referencelight sources are expensive, so this implementation may be lessexpensive to implement. In between each of the recordings, the referencesource may then be moved to the required new recording position.

In a third embodiment, the lens may comprise three distinctive hologramfilms, recorded separately and then assembled inside the lens. Thisimplementation has the advantages of removing the risk of parasiticlight between the recording zones.

In embodiments, the projection system may project as many images asthere are recording areas/zones, such that each of the images isredirected towards a different vertical eyebox location. In anembodiment, the MEMS-scanning projector may scan a larger field in thevertical axis and “paint” the images successively, and in a continuousscan, into each recording zone. A scan from top to bottom of thecumulative vertical recording zones may be considered to be a completescan pass. It will be understood that a bottom to top, left to right,right to left or other scan pattern may be used, in practice. In theillustration shown in FIG. 5A, three recording zones 521, 523, 525 areshown. It will be understood by one of skill in the art upon reviewingthe disclosure herein, that more or fewer than three recording zones maybe used. In an embodiment, the three zones 521, 523, 525 are part of oneprojection area 522. Thus, the recording zones may be projected in asingle scan to the projection area, in succession, as if one image wasbeing projected. As long as a recording zone is projected in at least 30Hz, a user should be able to see the image. However, projection of atleast 60 Hz may be used to mitigate the appearance of flicker. Thenumber of recording zones may depend on the height of the lens, thefitting height, scan rate, or average pupil size. Those users with largepupils may naturally be able to view multiple eyeboxes. Thus, therecording zones typically need to be of sufficient height so that theuser, will see only one at a time, to avoid double images or shadowimages.

In another embodiment, it may be desirable for a user to see more thanone eyebox, depending on the goals of the augmented reality system. Ifone eyebox per user/per glass is desired, then one image may bedisplayed. This embodiment prevents double images. However, otherembodiments allow the user to see different images in two or moreeyeboxes. In this case, each desired image may continue to be projectedin its respective eyebox. The user will need to change their gazelocation, however, to see the different images. In another embodiment,the image may be projected into all available eyeboxes so that the usermay see the image regardless of gaze direction. When different imagesare projected into different eyeboxes, it may be important that theeyeboxes do not overlap.

In an embodiment, different images may be projected into differentrecording zones. For instance, if the user launches an application forbicycling, the application may automatically select recording zone 523as a default, assuming that the user will be looking straight ahead intothe distance, while cycling. For a cooking application, recording zone525 may be selected as the default to accommodate a user lookingdownwards at the cookbook or kitchen work surface. An embodiment mayallow the user to select the preferred recording zone using a userinterface application in communication with the HWD, or using physicalor virtual buttons on the HWD, to be discussed more fully, below.

In an embodiment, the HWD may be fitted with eye gaze technology (notshown). The HWD may be trained or configured for the user for variouseye movement, head tilt, or application scenarios. The HWD may also befitted with a gyroscope to identify head tilt. In an embodiment, the HWDmay identify when the user is gazing upward, or downward, andautomatically adjust the projected recording area. In an embodiment,recording areas not being viewed or selected may be disabled. Theprojector may scan through the recording zones, but turn the projector(e.g., light source) off for the disabled recording areas. Disabling ofrecording zones not being viewed will save on power for the device,because only one light source will be used to paint the image in asingle eyebox.

In an embodiment, an optimization mechanism allows the user to first fitthe device, with or without explicit selection of the eyebox area. Whenthe eyebox is selected (e.g., the natural eyebox or a selected eyebox),other eyebox images, e.g., in different recording zones, may bedisabled. When implemented with the IPD mechanism, as discussed above,there may be additional horizontal eyeboxes painted to accommodate thevariances in IPD, but only one vertical recording zone enabled.

In an embodiment combining both the IPD and vertical adjustment, thevertical positioning of the eyebox, in addition to the horizontalimplementation for the IPD compensation, may utilize the followingrecording implementation. A recording implementation effectivelycombines both volume holographic recording technique (and limitation,due to wavelength-based light cross talk for example) and surface-basedholographic techniques. For instance, each time a multiple wavelength ata specific, position on the lens is recorded, the hologram is recorded xtimes, where x is the number of wavelengths. For example, a volumehologram may be recorded three times at three independent positions onthe lens/hologram.

FIG. 5B illustrates a vertical and horizontal adaption of eyeboxes,according to an embodiment. As discussed above, three vertical eyeboxes,or recording zones, 521-1, 523-1, and 525-1 may be available for thelens 520B, similar to zones 521, 523, 525 in FIG. 5A. In this example,zone 521-1 may also include three horizontal eyeboxes 521A-C. Asdiscussed above, horizontal zones may be projected with differentwavelengths onto a volume holographic lens to accommodate variances inuser IPD. Similarly, vertical zone 523-1 may include three horizontaleyeboxes 523A-C. And vertical zone 525-1 may include three horizontaleyeboxes 525A-C. As discussed above, once a vertical zone has beenselected, for instance zone 523-1, zones 521-1 and 525-1 may bedisabled. Thus, when a virtual image is projected onto lens 520B threewavelengths of the image are displayed simultaneously to horizontalzones 523A-C. In this embodiment, the user's head tilt, verticalpreference and personal IPD may be accommodated. Further, as the usertracks left and right, the virtual image may smoothly transition backand forth, from eyeboxes 523A, 523B, 523C.

FIG. 6 is a diagram illustrating a manual fitting method 600, accordingto an embodiment. In an embodiment, a user may utilize a mobile device,or other compute node, 675 to manually select a vertical fitting eyebox.A user may launch a vertical fitting adjustment application 685 with agraphical user interface component. The user may select vertical fittingeyebox settings in the application at block 610. The eyebox fittingapplication communicates with the HWD. In an embodiment, responsive tothe launch of the fitting application 685, the HWD may present a set oftest images in each of the vertical eyeboxes, successively, in block620. The user may select each of the eyeboxes where the image iscomfortably viewed, in block 630. The user may also provide feedback ifnone of the images is viewable, and the application 685 may give theuser advice on head tilt, eyewear adjustments, etc., until the user isable to see the virtual image in at least one eyebox. Once the viewableeyebox(es) are identified, the fitting application may scroll throughthe images again for the viewable eyeboxes, and allow the user to selecta preferred eyebox, in block 640. If only one eyebox is viewable, block640 may optionally be skipped and the viewable eyebox may beautomatically selected for the user. It will be understood that when theHWD implements the IPD mechanism, as described above, that anadjustments or configuration for horizontal eyeboxes may not benecessary, because, all horizontal eyeboxes may be projected indifferent wavelengths. However, an initial IPD measurement of the usermay be sent to the HWD as a baseline estimate.

FIG. 7 is a diagram illustrating an automatic adjustment method 700,according to an embodiment. In an embodiment, a user may utilize amobile device, or other compute node, 775 to allow the HWD toautomatically select a horizontal fitting eyebox, appropriate for theuser IPD. A user may launch an automatic fitting adjustment application785 with a graphical user interface (GUI) component. The user maymeasure their IPD and select the closest available IPD lens for thedisplay system, in block 710. The user may manually enter both theirmeasured IPD and that of the selected lens, in block 720. In practice, auser may receive their IPD measurement from an optometrist or otherspecialist. If this known measurement is not available, a user may use aruler specialized for IPD measurements to determine their IPD. An HWDmay be bundled with an inexpensive ruler and instructions for the user,if desired. In an example, the user may have an IPD of 63.2 mm, but thelens may have an available IPD of 64 mm. The lens may have multiple IPDoptions, which may be selected in a drop down box or other method, inthe GUI. The fitting application 785 may calculate the optimum imageshift to compensate the difference between the user's IPD and the IPD ofthe system, in block 730. The HWD system may implement the shift andstore the new image location parameters and updates the display systemdefaults, in block 740. A horizontal, or lateral, IPD adjustment maytypically be applied before vertical adjustment, for a better fit.

In an embodiment, adjustments for eyeboxes may be performed dynamically,after an initial configuration. For instance, a user may have selected acenter eyebox based on comfort, but is using an application thatrequires head movement. A gaze tracker and/or gyroscope in the HWD mayidentify a horizontal and vertical movement or change in gaze andautomatically adjust the projected eyebox. When using the IPD mechanismof Application '147, horizontal eye movement may not be affected due totransitioning from one wavelength eyebox to another. Eye gaze changes ina horizontal movement may identify an optimal horizontal eyebox, whenimplemented, but may be difficult to assess. In an embodiment, one ormore of the projected wavelengths may be disabled based on the user'sapparent gaze location. In an embodiment, the HWD may have a physical orvirtual button that when pressed may initiate a change in eyebox. Wheninitiated, the adaption may be automatic, or provide interactive promptsto the user to determine the desired changes. The interaction may bepart of the experience with the HWD, e.g., prompts appearing in aviewable location on the lens, or part of a GUI on a connected device.

FIG. 8 illustrates a block diagram of an example machine 800 upon whichany one or more of the techniques (e.g., methodologies) discussed hereinmay perform. In alternative embodiments, the machine 800 may operate asa standalone device or may be connected (e.g., networked) to othermachines. Machine 800 may be used to implement the GUI applications forfit adaption, or as a server in communication, with HWD to provide theAR images. It will be understood that the HWD may include somecomponents of machine 800, but not necessarily all of them. In anetworked deployment, the machine 800 may operate in the capacity of aserver machine, a client machine, or both in server-client networkenvironments. In an example, the machine 800 may act as a peer machinein peer-to-peer (P2P) (or other distributed) network environment. Themachine 800 may be a personal computer (PC), a tablet PC, a set-top box(STB), a personal digital assistant (PDA), a mobile telephone, a webappliance, a network router, switch or bridge, or any machine capable ofexecuting instructions (sequential or otherwise) that specify actions tobe taken by that machine. Further, while only a single machine isillustrated, the term “machine” shall also be taken to include anycollection of machines that individually or jointly execute a set (ormultiple sets) of instructions to perform any one or more of the,methodologies discussed herein, such as cloud computing, software as aservice (SaaS), other computer cluster configurations.

Examples, as described herein, may include, or may operate by, logic ora number of components, or mechanisms. Circuitry is a collection ofcircuits implemented in tangible entities that include hardware (e.g.,simple circuits, gates, logic, etc.). Circuitry membership may beflexible over time and underlying hardware variability. Circuitriesinclude members that may, alone or in combination, perform specifiedoperations when operating. In an example, hardware of the circuitry maybe immutably designed to carry out a specific operation (e.g.,hardwired). In an example, the hardware of the circuitry may includevariably connected physical components (e.g., execution units,transistors, simple circuits, etc.) including a computer readable mediumphysically modified (e.g., magnetically, electrically, moveableplacement, of invariant massed particles, etc.) to encode instructionsof the specific operation. In connecting the physical components, theunderlying electrical properties of a hardware constituent are changed,for example, from an insulator to a conductor or vice versa. Theinstructions enable embedded hardware (e.g., the execution units or aloading mechanism) to create members of the circuitry in hardware viathe variable connections to carry out portions of the specific operationwhen in operation. Accordingly, the computer readable medium iscommunicatively coupled to the other components of the circuitry whenthe device is operating. In an example, any of the physical componentsmay be used in more than one member of more than one circuitry. Forexample, under operation, execution units may be used in a first circuitof a first circuitry at one point in time and reused by a second circuitin the first circuitry, or by a third circuit in a second circuitry at adifferent time.

Machine (e.g., computer system) 800 may include a hardware processor 802(e.g., a central processing unit (CPU), a graphics processing unit(GPU), a hardware processor core, or any combination thereof), a mainmemory 804 and a static memory 806, some or all of which may,communicate with each other via an interlink (e.g., bus) 808. Themachine 800 may further include a display unit 810, an alphanumericinput device 812 (e.g., a keyboard), and a user interface (UI)navigation device 814 (e.g., a mouse). In an example, the display unit810, input device 812 and UI navigation device 814 may be a touch screendisplay. The machine 800 may additionally include a storage device(e.g., drive unit) 816, a signal generation device 818 (e.g., aspeaker), a network interface device 820, and one or more, sensors 821,such as a global positioning system (GPS) sensor, compass,accelerometer, or other sensor. The machine 800 may include an outputcontroller 828, such as a serial (e.g., universal serial bus (USB),parallel, or other wired or wireless (e.g., infrared (IR), near fieldcommunication (NFC), etc.) connection to communicate or control one ormore peripheral devices (e.g., a printer, card reader, etc.).

The storage device 816 may include a machine readable medium 822 onwhich is stored one, or more sets of data structures or instructions 824(e.g., software) embodying or utilized by any one or more of thetechniques or functions described herein. The instructions 824 may alsoreside, completely or at least partially, within the main memory 804,within static memory 806, or within the hardware processor 802 duringexecution thereof by the machine 800. In an example, one or anycombination of the hardware processor 802, the main memory 804, thestatic memory 806, or the storage device 816 may constitute machinereadable media.

While the machine readable medium 822 is illustrated as a single medium,the term “machine readable medium” may include a single medium ormultiple media (e.g., a centralized or distributed database, and/orassociated caches and servers) configured to store the one or moreinstructions 824.

The term “machine readable medium” may include any medium that iscapable of storing, encoding, or carrying instructions for execution bythe machine 800 and that cause the machine 800 to perform any one ormore of the techniques of the present disclosure, or that is capable ofstoring, encoding or carrying data structures used by or associated withsuch instructions. Non-limiting machine readable medium examples mayinclude solid-state memories, and optical and magnetic media. In anexample, a massed machine readable medium comprises a machine readablemedium with a plurality of particles having invariant (e.g., rest) mass.Accordingly, massed machine-readable media are not transitorypropagating signals. Specific examples of massed machine readable mediamay include: non-volatile memory, such as semiconductor memory devices(e.g., Electrically Programmable Read-Only Memory (EPROM), ElectricallyErasable Programmable Read-Only Memory (EEPROM)) and flash memorydevices; magnetic disks, such, as internal hard disks and removabledisks; magneto-optical disks, and CD-ROM and DVD-ROM disks.

The instructions 824 may further be transmitted or received over acommunications network 826 using a transmission medium via the networkinterface device 820 utilizing any one of a number of transfer protocols(e.g., frame relay, internet protocol (IP), transmission controlprotocol (TCP), user datagram protocol (UDP), hypertext transferprotocol (HTTP), etc.). Example communication networks may include alocal area network (LAN), a wide area network (WAN), a packet datanetwork (e.g., the Internet), mobile telephone networks (e.g., cellularnetworks), Plain Old Telephone (POTS) networks, and wireless datanetworks (e.g., Institute of Electrical and Electronics Engineers (IEEE)802.11 family of standards known as Wi-Fi®, IEEE 802.16 family ofstandards known as WiMax®), IEEE 802.15.4 family of standards,peer-to-peer (P2P) networks, among others. In an example, the networkinterface device 820 may include one or more physical jacks (e.g.,Ethernet, coaxial, or phone jacks) or one or more antennas to connect tothe communications network 826. In an example, the network interfacedevice 820 may include a plurality of antennas to wirelessly communicateusing at least one of single-input multiple-output (SIMO),multiple-input multiple-output (MIMO), or multiple-input single-output(MISO) techniques. The term “transmission medium” shall be taken toinclude any intangible medium that is capable of storing, encoding orcarrying instructions for execution by the machine 800, and includesdigital or analog communications signals or other intangible medium tofacilitate communication of such software.

FIG. 9 illustrates a head worn device in the form of smartglasses,according to an embodiment. In an embodiment, the smartglasses 910 arenot much bigger or heavier than a regular pair of eyeglasses. Therefore,a user may feel more comfortable wearing them, both physically andaesthetically. In an embodiment, smartglasses 910 include a battery 950.It will be understood that the battery 950 may be replaceable orrechargeable via wired or wireless means. The battery 950 may providepower to the projection system 940 via wires embedded in the plasticframe, and therefore unseen. A MEMS projection system 940 maycommunicate wirelessly to a server or mobile device to receive ARcontent for display. The MEMS projection system 940 may be coupled tophysical buttons or switches 941, for instance for power or othercontrols. The MEMS projector 940 includes at least one light source 942.As discussed above the MEMS projector system 940 may retrieve therecording information from polymer memory to project the light source atthe appropriate angle for AR content 920. In the example shown, the userviews real world images through the transparent holographic lenses 930,and may view the AR content 920 when gazing down. In an embodiment, theMEMS projection system 940 may be coupled to a gaze tracker. The gazetracker differs from the projection system 940 because it is effectivelya camera system aimed at the user's eye rather than the lens todetermine at what angle the user's gaze is directed The gaze tracker maybe integrated with the projector system 940 using a non-visible laser tothe projection system that shines light onto the eye and the reflectedlight, reflected by the eye, reaches a photosensor, such as aphotodiode, placed as well in the projection system. In anotherembodiment, the gaze tracker may be separate from the projector system940, but in communication with components on the smartglasses 910. Thegaze tracker may use a frame of reference angle based on the mountingconfiguration on the smartglasses 910.

ADDITIONAL NOTES AND EXAMPLES

Examples may include subject matter such as a method, means forperforming acts of the method, at least one machine-readable mediumincluding instructions that, when performed by a machine cause themachine to performs acts of the method, or of an apparatus or system foradjusting the eyebox of a head worn display displaying augmented images,according to embodiments and examples described herein.

Example 1 is a head worn device for providing virtual images to a user,comprising: a holographic lens coupled to the head worn device, theholographic lens positioned to enable the user to view a virtual imageon the holographic lens; and a projector coupled to the head worn deviceto project the virtual image onto the holographic lens in a projectionarea of the holographic lens, wherein the projection area includes atleast two vertically adjacent recording zones, and wherein the projectoris to project the virtual image into the at least two verticallyadjacent recording zones, wherein an eyebox for the user is based inpart on a pantoscopic tilt angle of the user's pupil with respect to theholographic lens, and an eye relief distance measurement of the user'seye surface with respect to the holographic lens, and wherein the eyeboxcorresponds to at least one of the at least two vertically adjacentrecording zones.

In Example 2, the subject matter of Example 1 optionally includeswherein the projector is a microelectromechanical system usingholographic technique for projection.

In Example 3, the subject matter of any one or more of Examples 1-2optionally include wherein responsive to a selection of one of the atleast two vertically adjacent recording zones that corresponds to theeyebox, disabling projection into each vertically adjacent recordingzone that has not been selected, wherein disabling is to turn off alight source of the projector when projecting into unselected recordingzones.

In Example 4, the subject matter of Example 3 optionally includeswherein the projecting into the projection area is to paint a continuousscan into the projection areas, wherein a complete scan pass includespainting the virtual image successively in one pass for each of thevertically adjacent recording zones in the projection area, and whereindisabling of a recording zone is to turn off the light source during thescan of the unselected recording zones, and turn on the light sourceduring the scan of the selected recording zone in each scan pass.

In Example 5, the subject matter of any one or more of Examples 1-4optionally include wherein responsive to a selection of more than one ofthe at least two vertically adjacent recording zones that corresponds tothe eyebox, disabling projection into each vertically adjacent recordingzone that has not been selected, wherein disabling is to turn off alight source of the projector when projecting into unselected recordingzones.

In Example 6, the subject matter of Example 5 optionally includeswherein the more than one of the at least two vertically adjacentrecording zones is selected, responsive to an indication that the useris able to see the more than one of the at least two vertically adjacentrecording zones, and wherein the projector is to project a differentimage to at least one of the selected vertically adjacent recordingzones.

In Example 7, the subject matter of any one or more of Examples 1-6optionally include wherein selection of the vertically adjacentrecording zone corresponding to the eyebox is responsive to receiving auser selection.

In Example 8, the subject matter of Example 7 optionally includeswherein selection of a horizontal location of the eyebox for projectionin the selected vertically adjacent recording zone is based on areceived horizontal image shift information corresponding to the user'sinter-pupillary distance.

In Example 9, the subject matter of any one or more of Examples 7-8optionally include wherein the eyebox location is to be dynamicallyadjusted responsive to identifying eye gaze or head tilt of the user.

In Example 10, the subject matter of any one or more of Examples 1-9optionally include wherein selection of the vertically adjacentrecording zone corresponding to the eyebox is performed automatically.

In Example 11, the subject matter of any one or more of Examples 1-10optionally include wherein the projector further comprises: a wavelengthgenerator to project the virtual image onto at least two horizontallyadjacent areas in each vertically adjacent recording zone, wherein theprojection to each horizontally adjacent area is at a wavelengthdifferent from another horizontally adjacent area in the same verticallyadjacent recording zone.

In Example 12, the subject matter of Example 11 optionally includeswherein responsive to a selection of one of the at least two verticallyadjacent recording zones that corresponds to the eyebox, disablingprojection into each vertically adjacent recording zone that has notbeen selected, wherein disabling is to turn off a light source of theprojector when projecting into unselected recording zones, andcontinuing to project into each of the horizontally adjacent areas inthe selected recording zone to accommodate left and right movement ofthe user's gaze.

In Example 13, the subject matter of Example 12 optionally includeswherein the projecting into the projection area is to paint a continuousscan into the projection areas, wherein a complete scan pass includespainting the virtual image successively in one pass for each of thevertically adjacent recording zones in the projection area, and whereindisabling of a recording zone is to turn off the light source during thescan of the unselected recording zones, and turn on the light sourceduring the scan of the selected recording zone in each scan pass.

In Example 14, the, subject matter of any one or more of Examples 11-13optionally include wherein selection of the vertically adjacentrecording zone corresponding to the eyebox is responsive to receiving auser selection, and wherein the user selection also includes informationcorresponding to the user's inter-pupillary distance.

In Example 15, the subject, matter of any one or more of Examples 11-14optionally include wherein selection of the vertically adjacentrecording zone corresponding to the eyebox is performed automatically.

In Example 16, the subject matter of any one or more of Examples 1-15optionally include wherein the holographic lens is positioned so that afirst eye of the user may view the eyebox, and wherein the head worndevice further comprises, a second optical lens for a second eye of theuser, and wherein projection to the eyebox is based at least on aninter-pupillary distance for the first and second eye of the user,optics characteristics of the head worn device, and user preferences.

Example 17 is a method for adapting fit of a head worn device,comprising: presenting a user of a head worn device with a series oftest images, the test images to be projected in at least two verticallyadjacent recording zones of the head worn device; responsive toidentification by the user, in a graphical user interfacecommunicatively coupled to the head worn device, which images of theseries of test images are seen by the user as projected in the head worndevice, determining an eyebox location of the head worn device, based onwhich images are seen by the user; and sending the eyebox location tothe head worn device to enable the head worn device to updateconfiguration parameters associated with projection locations.

In Example 18, the subject matter of Example 17 optionally includespresenting the user with input fields in the graphical user interface,the input fields enabling entry of an inter-pupillary distancecorresponding the user, and an inter-pupillary distance parameterassociated with a configuration of the head worn device, responsive toentry into the input fields, calculating an horizontal image shift tocompensate for differences in the user's inter-pupillary distanceentered and the inter-pupillary distance parameter associated with theconfiguration of the head worn device; and sending the horizontal imageshift to the head worn device to enable the head worn device to updateconfiguration parameters associated with horizontal projectionlocations.

In Example 19, the subject matter of Example 18 optionally includeswherein the entry of an inter-pupillary distance is performed beforepresenting the user with the series of test images.

In Example 20, the subject matter of any one or more of Examples 17-19optionally include presenting the user of the head worn device with asecond series of test images, the test images to be projected in atleast two vertically adjacent recording zones of the head worn device;repeating the determining of the eyebox location and sending the eyeboxlocation, based in part on user responses to the second series of testimages.

Example 21 is at least one non-transitory computer readable mediumhaving instructions stored thereon, the instructions when executed on amachine cause the machine to: present a user of a head worn device witha series of test images, the test images to be projected in at least twovertically adjacent recording zones of the head worn device; determinean eyebox location of the head worn device, based on which images areseen by the user, responsive to identification by the user, in agraphical user interface communicatively coupled to the head worndevice, which images of the series of test images are seen by the useras projected in the head worn device; and send the eyebox location tothe head worn device to enable the head worn device to updateconfiguration parameters associated with projection locations.

In Example 22, the subject matter of Example 21 optionally includesinstructions to: present the user with input fields in the graphicaluser interface, the input fields enabling entry of an inter-pupillarydistance corresponding the user, and an inter-pupillary distanceparameter associated with a configuration of the head worn device;calculate an horizontal image shift to compensate for differences in theuser's inter-pupillary distance entered and the inter-pupillary distanceparameter associated with the configuration of the head worn device,responsive to entry into the input fields, and send the horizontal imageshift to the head worn device to enable the head worn device to updateconfiguration parameters associated with horizontal projectionlocations.

In Example 23, the subject matter of any one or more of Examples 21-22optionally include instructions to: present the user of the head worndevice with a second series of test images, the test images to beprojected in at least two vertically adjacent recording zones of thehead worn device; repeat the instructions to determine the eyeboxlocation and send the eyebox location, based in part on user responsesto the second series of test images.

Example 24 is at least one non-transitory computer readable mediumhaving instructions stored thereon, the instructions when executed on ahead worn device cause the head worn device to: project a virtual imageon a holographic lens in a projection area of the holographic lens,wherein the projection area includes at least two vertically adjacentrecording zones, and wherein the projector is to project, the virtualimage into the at least two vertically adjacent recording zones, whereinan eyebox for the user is based in part on a pantoscopic tilt angle ofthe user's pupil with respect to the holographic lens, and an eye reliefdistance measurement of the user's eye surface with respect to theholographic lens, and wherein the eyebox corresponds to at least one ofthe at least two vertically adjacent recording zones.

In Example 25, the subject matter of Example 24 optionally includesinstructions to disable projection into each vertically adjacentrecording zone that has not been selected, wherein disabling is to turnoff a light source of the projector when projecting into unselectedrecording zone, responsive to a selection of one of the at least twovertically adjacent recording zones that corresponds to the eyebox.

Example 26 is a system for adapting fit of a head worn device,comprising: means for presenting a user of a head worn device with aseries of test images, the test images to be projected in at least twovertically adjacent recording zones of the head worn device; means fordetermining an eyebox location of the head worn device based on whichimages are seen by the user, responsive to identification by the user,in a graphical user interface communicatively coupled to the head worndevice, which images of the series of test images are seen by the useras projected in the head worn device; and means for sending the eyeboxlocation to the head worn device to enable the head worn device toupdate configuration parameters associated with projection locations.

In Example 27, the subject matter of Example 26 optionally includesmeans for presenting the user with input fields in the graphical userinterface, the input fields enabling entry of an inter-pupillarydistance corresponding the user, and an inter-pupillary distanceparameter associated with a configuration of the head worn device; meansfor calculating an horizontal image shift to compensate for differencesin the user's inter-pupillary distance entered and the inter-pupillarydistance parameter associated with the configuration of the head worndevice, responsive to entry into the input fields; and means for sendingthe horizontal image shift to the head worn device to enable the headworn device to update configuration parameters associated withhorizontal projection locations.

In Example 28, the subject matter of Example 27 optionally includeswherein the entry of an inter-pupillary distance is performed beforepresenting the user with the series of test images.

In Example 29, the subject, matter of any one or more of Examples 26-28optionally include means for presenting the user of the head worn devicewith a second series of test images, the test images to be projected inat least two vertically adjacent recording zones of the head worndevice; means for repeating the determining of the eyebox location andsending the eyebox location, based in part on user responses to thesecond series of test images.

Example 30 is a method for providing virtual images to a user, themethod comprising: projecting a virtual image on a holographic lens in aprojection area of the holographic lens, wherein the projection areaincludes at least two vertically adjacent recording zones, and whereinthe projector is to project the virtual image into the at least twovertically adjacent recording zones, wherein an eyebox for the user isbased in part on a pantoscopic tilt angle of the user's pupil withrespect to the holographic lens, and an eye relief distance measurementof the user's eye surface with respect to the holographic lens, andwherein the eyebox corresponds to at least one of the at least twovertically adjacent recording zones.

In Example 31, the subject matter of Example 30 optionally includeswherein the projector is a microelectromechanical system usingholographic technique for projection.

In Example 32, the subject matter of any one or more of Examples 30-31optionally include wherein responsive to a selection of one of the atleast two vertically adjacent recording zones that corresponds to theeyebox, the method further comprises disabling projection into eachvertically adjacent recording zone that has not been, selected, whereindisabling is to turn off a light source of the projector when projectinginto unselected recording zones.

In Example 33, the subject, matter of Example 32 optionally includeswherein the projecting further comprises: painting a continuous scaninto the projection area, wherein a complete scan pass includes paintingthe virtual image successively in one pass for each of the verticallyadjacent recording zones in the projection area, and wherein disablingof a recording zone is to turn off the light source during the scan ofthe unselected recording zones, and turn on the light source during thescan of the selected recording zone in each scan pass.

In Example 34, the subject matter of any one or more of Examples 30-33optionally include wherein responsive to a selection of more than one ofthe at least two vertically adjacent recording zones that corresponds tothe eyebox, disabling projection into each vertically adjacent recordingzone that has not been selected, wherein disabling is to turn off alight source of the projector when projecting into unselected recordingzones.

In Example 35, the subject matter of Example 34 optionally includeswherein the more than one of the at least two vertically adjacentrecording zones is selected, responsive to an indication that the useris able to see the more than one of the at least two vertically adjacentrecording zones, and wherein the projector is to project a differentimage to at least one of the selected vertically adjacent recordingzones.

In Example 36, the subject matter of any one or more of Examples 30-35optionally include selecting the vertically adjacent recording zonecorresponding to the eyebox, responsive to receiving a user selection.

In Example 37, the subject matter of Example 36 optionally includesselecting a horizontal location of the eyebox for projection in theselected vertically adjacent recording zone based on a receivedhorizontal image shift information corresponding to the user'sinter-pupillary distance.

In Example 38, the subject matter of any one or more of Examples 36-37optionally include dynamically adjusting the eyebox location, responsiveto identifying eye gaze or head tilt of the user.

In Example 39, the subject matter of any one or more of Examples 30-38optionally include automatically selecting the vertically adjacentrecording zone corresponding to the eyebox.

In Example 40, the subject matter of any one or more of Examples 30-39optionally include projecting the virtual image onto at least twohorizontally adjacent areas in each vertically adjacent recording zone,wherein the projection to each horizontally, adjacent area is at awavelength different from another horizontally adjacent area in the samevertically adjacent recording zone.

In Example 41, the subject matter of Example 40 optionally includesdisabling projection into each vertically adjacent recording zone thathas not been selected, responsive to a selection of one of the at leasttwo vertically adjacent recording zones that corresponds to the eyebox,wherein disabling is to turn off a light source of the projector whenprojecting into unselected recording zones, and continuing to projectinto each of the horizontally adjacent areas in the selected recordingzone to accommodate left and right movement of the user's gaze.

In Example 42, the subject matter of Example 41 optionally includeswherein the projecting into the projection area comprises: painting acontinuous scan into the projection areas, wherein a complete scan passincludes painting the virtual image successively in one pass for each ofthe vertically adjacent recording, zones in the projection area, andwherein disabling of a recording zone is to turn off the light sourceduring the scan of the unselected recording zones, and turn on the lightsource during the scan of the selected recording zone in each scan pass.

In Example 43, the subject matter of any one or more of Examples 40-42optionally include selecting the vertically adjacent recording zonecorresponding to the eyebox, responsive to receiving a user selection,and wherein the user selection also includes information correspondingto the user's inter-pupillary distance.

In Example 44, the subject matter of any one or more of Examples 40-43optionally include automatically selecting the vertically adjacentrecording zone corresponding to the eyebox is performed.

In Example 45, the subject matter of any one or more of Examples 30-44optionally include wherein the holographic lens is positioned so that afirst eye of the user may view the eyebox, and wherein the head worndevice further comprises, a second optical lens for a second eye of theuser, and wherein projection to the eyebox is based at least on aninter-pupillary distance for the first and second eye of the user,optics characteristics of the head worn device, and user preferences.

Example 46 is a non-transitory computer readable storage medium, havinginstructions stored thereon, the instructions when executed on a headworn device, cause the device to perform that acts of any of Examples 30to 45.

Example 47 is a system configured to perform operations of any one ormore of Examples 1-46.

Example 48 is a method for performing operations of any one or more ofExamples 1-46.

Example 49 is at least one machine readable medium includinginstructions that, when executed by a machine cause the machine toperform the operations of any one or more of Examples 1-46.

Example 50 is a system comprising means for performing the operations ofany one or more of Examples 1-46.

The techniques described herein are not limited to any particularhardware or software configuration; they may find applicability in anycomputing, consumer electronics, or processing environment. Thetechniques may be implemented in hardware, software, firmware or acombination, resulting in logic or circuitry which supports execution orperformance of embodiments described herein.

For simulations, program code may represent hardware using a hardwaredescription language or another functional description language whichessentially provides a model of how designed hardware is expected toperform Program code may be assembly or machine language, or data thatmay be compiled and/or interpreted. Furthermore, it is common in the artto speak of software, in one form or another as taking an action orcausing a result. Such expressions are merely a shorthand way of statingexecution of program code by a processing system which causes aprocessor to perform an action or produce a result.

Each program may be implemented in a high level procedural, declarative,and/or object-oriented programming language to communicate with aprocessing system. However, programs may be implemented in assembly ormachine language, if desired. In any case, the language may be compiledor interpreted.

Program instructions may be used to cause a general-purpose orspecial-purpose processing system that is programmed with theinstructions to perform the operations described herein. Alternatively,the operations may be performed by specific hardware components thatcontain hardwired logic for performing the operations, or by anycombination of programmed computer components and custom hardwarecomponents. The methods described herein may be provided as a computerprogram product, also described as a computer or machine accessible orreadable medium that may include one or more machine accessible storagemedia having stored thereon instructions that may be used to program aprocessing system or other electronic device to perform the methods.

Program code, or instructions, may be stored in, for example, volatileand/or non-volatile memory, such as storage devices and/or an associatedmachine readable or machine accessible medium including solid-statememory, hard-drives, floppy-disks, optical storage, tapes, flash memory,memory sticks, digital video disks, digital versatile discs (DVDs),etc., as well as more exotic mediums such as machine-accessiblebiological state preserving storage. A machine readable medium mayinclude any mechanism for storing, transmitting, or receivinginformation in a form readable by a machine, and the medium may includea tangible medium through which electrical, optical, acoustical or otherform of propagated signals or carrier wave encoding the program code maypass, such as antennas, optical fibers, communications interfaces, etc.Program code may be transmitted in the form of packets, serial data,parallel, data, propagated signals, etc., and may be used in acompressed or encrypted format.

Program code may be implemented in programs executing on programmablemachines such as mobile or stationary computers, personal digitalassistants, smart phones, mobile Internet devices, set top boxes,cellular telephones and, pagers, consumer electronics devices (includingDVD players, personal video recorders, personal video players, satellitereceivers, stereo receivers, cable TV receivers), and other electronicdevices, each including a processor, volatile and/or non-volatile memoryreadable by the processor, at least one input device and/or one or moreoutput devices. Program code may be applied to the data entered usingthe input device to perform the described embodiments and to generateoutput information. The output information may be applied to one or moreoutput devices. One of ordinary skill in the art may appreciate thatembodiments of the disclosed subject, matter can be practiced withvarious computer system configurations, including multiprocessor ormultiple-core processor systems, minicomputers, mainframe computers, aswell as pervasive or miniature computers or processors that may beembedded into virtually any device. Embodiments of the disclosed subjectmatter can also be practiced in distributed computing environments,cloud environments, peer-to-peer or networked microservices, where tasksor portions thereof may be performed by remote processing devices thatare linked through a communications network.

A processor subsystem may be used to execute the instruction on themachine-readable or machine accessible media. The processor subsystemmay include one or more processors, each with one or more cores.Additionally, the processor subsystem may be disposed on one or morephysical devices. The processor subsystem may include one or morespecialized processors, such as a graphics processing unit (GPU), adigital signal processor (DSP), a field programmable gate array (FPGA),or a fixed function processor.

Although operations may be described as a sequential process, some ofthe operations may in fact be performed in parallel, concurrently,and/or in a distributed environment, and with program code storedlocally and/or remotely for access by single or multi-processormachines. In addition, in some embodiments the order of operations maybe rearranged without departing from the spirit of the disclosed subjectmatter. Program code may be used by or in conjunction with embeddedcontrollers.

Examples, as described herein, may include, or may operate on,circuitry, logic or a number of components, modules, or mechanisms.Modules may be hardware, software, or firmware communicatively coupledto one or more processors in order to carry out the operations describedherein. It will be understood that the modules or logic may beimplemented in a hardware component or device, software or firmwarerunning on one or more processors, or a combination. The modules may bedistinct and independent components integrated by sharing or passingdata, or the modules may be subcomponents of a single module, or besplit among several modules. The components may be processes running on,or implemented on, a single compute node or distributed among aplurality of compute nodes running in parallel, concurrently,sequentially or a combination, as described more fully in conjunctionwith the flow diagrams in the figures. As such, modules may be hardwaremodules, and as such modules may be considered tangible entities capableof performing specified operations and may be configured or arranged ina certain manner. In an example, circuits may be arranged (e.g.,internally or with respect to external entities such as other circuits)in a specified manner as a module. In an example, the whole or part ofone or more computer systems (e.g., a standalone, client or servercomputer system) or one or more hardware processors may be configured byfirmware or software (e.g., instructions, an application portion, or anapplication) as a module that operates to perform specified operations.In an example, the software may reside on a machine-readable medium. Inan example, the software, when executed by the underlying hardware ofthe module, causes the hardware to perform the specified operations.Accordingly, the term hardware module is understood to encompass atangible entity, be that an entity that is physically constructed,specifically configured (e.g., hardwired), or temporarily (e.g.,transitorily) configured (e.g., programmed) to operate in a specifiedmanner or to perform part or all of any operation described herein.Considering, examples in which modules are temporarily configured, eachof the modules need not be instantiated at any one moment in time. Forexample, where the modules comprise a general-purpose hardware processorconfigured, arranged or adapted by using software; the general-purposehardware processor may be configured as respective different modules atdifferent times. Software may accordingly configure a hardwareprocessor, for example, to constitute a particular module at oneinstance of time and to constitute a different module at a differentinstance of time. Modules may also be software or firmware modules,which operate to perform the methodologies described herein.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to .a nonexclusive or, suchthat “A or B” includes “A but not B,” “B but not A,” and “A and B,”unless otherwise indicated. In the appended claims, the terms“including” and “in which” are used as the plain-English equivalents ofthe respective terms “comprising” and “wherein.” Also, in the followingclaims, the terms “including” and “comprising” are open-ended, that is,a system, device, article, or process that includes elements in additionto those listed after such a term in a claim are still deemed to fallwithin the scope of that claim. Moreover, in the following claims, theterms “first,” “second,” and “third,” etc. are used merely as labels,and are not intended to suggest a numerical order for their objects.

While this subject matter has been described with reference toillustrative embodiments, this description is not intended to beconstrued in, a limiting or restrictive sense. For example, theabove-described examples (or one or more aspects thereof) may be used incombination with others. Other embodiments may be used, such as will beunderstood by one of ordinary skill in the art upon reviewing thedisclosure herein. The Abstract is to allow the reader to quicklydiscover the nature of the technical disclosure. However, the Abstractis submitted with the understanding that it will not be used tointerpret or limit the scope or meaning of the claims.

1-16. (canceled)
 17. A method for adapting fit of a head worn device,comprising: presenting a user of a head worn device with a series oftest images, the series of test images to be projected in at least twovertically adjacent recording zones of the head worn device; responsiveto an identification, received from the user, of which images of theseries of test images are seen by the user as projected in the head worndevice, determining an eyebox location of the head worn device, based onwhich images of the series of test images are identified by the user;and sending the eyebox location to the head worn device to enable thehead worn device to update configuration parameters associated withprojection locations.
 18. The method as recited in claim 17, furthercomprising: presenting the user with input fields in a graphical userinterface communicatively coupled to the head worn device, the inputfields enabling entry of an inter-pupillary distance corresponding theuser, and an inter-pupillary distance parameter associated with aconfiguration of the head worn device; responsive to entry into theinput fields, calculating a horizontal image shift to compensate fordifferences in the user's inter-pupillary distance entered and theinter-pupillary distance parameter associated with the configuration ofthe head worn device; and sending the horizontal image shift to the headworn device to enable the head worn device to update configurationparameters associated with horizontal projection locations.
 19. Themethod as recited in claim 18, wherein the entry of the inter-pupillarydistance is performed before presenting the user with the series of testimages.
 20. The method as recited in claim 17, further comprising:presenting the user of the head worn device with a second series of testimages, the second series of test images to be projected in at least twovertically adjacent recording zones of the head worn device; andrepeating the determining of the eyebox location and sending the eyeboxlocation, based in part on user responses to the second series of testimages.
 21. At least one non-transitory computer readable medium havinginstructions stored thereon, the instructions when executed on a machinecause the machine to: present a user of a head worn device with a seriesof test images, the series of test images to be projected in at leasttwo vertically adjacent recording zones of the head worn device;responsive to an identification, input by the user in a graphical userinterface communicatively coupled to the head worn device, of whichimages of the series of test images are seen by the user as projected inthe head worn device, determine an eyebox location of the head worndevice, based on which images of the series of test images areidentified by the user; and send the eyebox location to the head worndevice to enable the head worn device to update configuration parametersassociated with projection locations.
 22. The medium as recited in claim21, further comprising instructions to: present the user with inputfields in the graphical user interface, the input fields enabling entryof an inter-pupillary distance corresponding the user, and aninter-pupillary distance parameter associated with a configuration ofthe head worn device; calculate a horizontal image shift to compensatefor differences in the inter-pupillary distance entered and theinter-pupillary distance parameter associated with the configuration ofthe head worn device, responsive to entry into the input fields; andsend the horizontal image shift to the head worn device to enable thehead worn device to update configuration parameters associated withhorizontal projection locations.
 23. The medium as recited in claim 21,further comprising instructions to: present the user of the head worndevice with a second series of test images, the second series of testimages to be projected in at least two vertically adjacent recordingzones of the head worn device; and repeat the instructions to determinethe eyebox location and send the eyebox location, based in part on userresponses to the second series of test images.
 24. (canceled) 25.(canceled)
 26. The medium as recited in claim 21, further comprisinginstructions to: determine, based on the identification, that the userhas identified a first recording zone and a second recording zone of theat least two vertically adjacent recording zones of the head worndevice; responsive to determining that the user has identified the firstrecording zone and the second recording zone, present the user of thehead worn device with a second series of test images, the second seriesof test images to be projected successively in the first recording zone,then the second recording zone; and repeat the instructions to determinethe eyebox location and send the eyebox location, based in part on userresponses to the second series of test images.
 27. The medium as recitedin claim 21, wherein, to present the user of the head worn device withthe series of test images, the instructions cause the machine to: causethe series of test images to be projected in only a first recording zoneof the at least two vertically adjacent recording zones of the head worndevice; and subsequent to projection of the series of test images inonly the first recording zone, cause the series of test images to beprojected in only a second recording zone of the at least two verticallyadjacent recording zones of the head worn device.
 28. A display systemfor providing virtual images to a user, comprising: a holographic lenscomprising a projection area that includes at least two verticallyadjacent recording zones; a projector configured to project virtualimages onto the projection area of the holographic lens; a processorconfigured to: receive an inter-pupillary distance value associated witha user; receive an inter-pupillary distance parameter associated with aconfiguration of the display system; calculate a horizontal image shiftto compensate for differences in the inter-pupillary distance valueassociated with the user and the inter-pupillary distance parameterassociated with the configuration of the display system; and causeconfiguration parameters of the display system associated withhorizontal projection locations of the projection area to be updatedbased on the horizontal image shift.
 29. The display system of claim 28,wherein the processor is configured to: cause a series of test images tobe projected in the at least two vertically adjacent recording zones ofthe projection area of the holographic lens; receive an identificationof images of the series of test images; determine an eyebox location ofthe projection area based at least in part on the identification of theimages of the series of test images; and cause configuration parametersof the display system associated with vertical projection locations ofthe projection area to be updated based on the eyebox location.
 30. Thedisplay system of claim 29, wherein the processor is configured to:determine that the identification corresponds to a first recording zoneand a second recording zone of the at least two vertically adjacentrecording zones; responsive to determining that the identificationcorresponds to the first recording zone and the second recording zone,cause a second series of test images to be projected in the firstrecording zone; after the second series of test images is projected inthe first recording zone, cause the second series of test images to beprojected in the second recording zone; and receive a secondidentification of second images of the second series of test images,wherein the eyebox location is determined based in part on the secondidentification of second images of the second series of test images. 31.The display system of claim 29, wherein, to cause the series of testimages to be projected in the at least two vertically adjacent recordingzones of the projection area of the holographic lens, the processor isconfigured to: cause the series of test images to be projected in only afirst recording zone of the at least two vertically adjacent recordingzones; and subsequent to projection of the series of test images in onlythe first recording zone, cause the series of test images to beprojected in only a second recording zone of the at least two verticallyadjacent recording zones.
 32. The display system of claim 29, whereinthe processor is configured to determine the eyebox location furtherbased on a pantoscopic tilt angle of a user's pupil with respect to theholographic lens.
 33. The display system of claim 32, wherein theprocessor is configured to determine the eyebox location based furtheron an eye relief distance measurement of the user's eye surface withrespect to the holographic lens.
 34. The display system of claim 29,wherein each of the at least two vertically adjacent recording zonescomprises at least two horizontally adjacent eyeboxes.
 35. The displaysystem of claim 34, wherein the projector, when projecting a virtualimage onto the projection area of the holographic lens, is configured toproject the virtual image onto a first eyebox of the at least twohorizontally adjacent eyeboxes at a first wavelength, and to project thevirtual image onto a second eyebox of the at least two horizontallyadjacent eyeboxes at a second wavelength that is different from thefirst wavelength.
 36. The display system of claim 28, furthercomprising: a head worn device comprising the holographic lens and theprojector.
 37. The display system of claim 28, wherein the projector isa microelectromechanical system (MEMS) holographic projector.